Dredge



Patnced Apr. ll, I899.

v.A. J. SEVERANCE.

D R E D G E (Application filed Mar. 22, 1898.)

3 Sheets-Sheet 2.

(No Model.)

$543 IKM/A awozwmg Tm: wams Farms ca. PHOTO-LIYHO., wasumm'cu, o. c.

v Patented Ap r. n, I899.

D R E D GE. (Application filed Mar. 22, leeaj 3 Sheets-Sheet. 3.

(No Model.)

V /l I 2 llll' ill ms scams PEI'ERS 50.. Pnm'oumoq WASNINGTON, o, c.

NITED STATES ASAHEL J. SE VERAN CE,

O F DENVER, COLORADO.

DREDG E.

SPECIFICATION forming part of Letters 7 Application. filed March 22,1898.

To all whom it may concern:-

Be it known that I, AsAHnL J. SEVERANOE, a citizen of the United Statesof America, residing at Denver, in the county of 'Arapahoe and State ofColorado, have invented certain new and useful Improvements in Dredges;and I do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying-drawings, and to .the letters and fig- 11 res ofreference marked thereon, which form a part of this specification.

My invention relates to improvements in dredges; and the objects of myinvention are, first, to provide a vacuum suction liftingdredgeespecially adapted to take up the gold and gold-carrying gravel and sandlying on the bed-rock of rivers; second, to provide a dredge that can beoperated in rapid-flowing rivers and that will take up and retain, bymeans of a vacuum suction-lift, all the loose rocks, gravel, sand, andgold lying on the bed of rivers; third, to provide a dredge that can beoperated in rivers of any reasonable depth Without losing the fineflour-gold and fine goldbearing sand While raisin ga load from thebedrock of a river through the Water to the deck of the dredge-boat,and, fourth, to provide a simple, durable, positively-operating dredgein which the gravel-lifting member is entirely free from finished movingmachinery or operating mechanism, and consequently cannot get out oforder, and in which the operating machinery can be safely housed andsecured on the deck of the dredge-boat whereit can be kept free fromcontact with and from the Wear of sand and gravel. I attain theseobjects by the mechanism illustrated in the accompanying drawings, inWhlQh- V Figure 1 is a side elevation of adredge embodying my invention.Fig. 2 is a plan view of the same. Fig. 3 is an end elevation of thefront or-vacuum-lift-tube end of the dredge. Fig. 4 is a side elevation,partially in section, of one of the anchors of the dredgeboat. Fig. 5 isa sectional View of the pivotal supporting-shaft for the cage andsweepbeam of the vacuum-tube and of the sheaves that support the tubehoisting and lowering ropes. Fig. 6 is a bottom plan View of the- PatentNo; 623,111, dated April 11, 899.

Serial No. 674,788. (No model-l suction end of the vacuum lift-tube,showing the double -door controlling the entrance to the tube. Fig. 7 isa vertical sectional view of the vacuum lift-tube.

Similar letters and figures of reference refer to similar partsthroughout the several iews. Referring to Fig. 1, A designates asuitable boat for supporting the various pieces of machinery andelements which make up the dredge. The front end B of the boat is curvedconcentric to a pivotal post- O, that is rigidly fixed to the boat inany suitable manner. This post stands vertically several feet high, andits top end is supported by the guy-ropes D. These guy-ropes are securedto the ring E, which is secured adjacent to the top end of the post, andthe ropes extend to the deck of the boat. At the top of the post Isecure a cap F, whichis adapted to form a' journal for the pin G. Cap Fcomprises a hood-shaped flangeportion which is adapted to fit over theend of the top of the post (see Fig. 5) and a long depending sleeveportion H, which is extended into the center of the post. The casting issecured to the post by suitable lagscreWs I. The sleeve. portion of thiscasting is adapted to form a suitable pivotal bearing for the pin G,which is extended and formed above its-head K into a horizontalcross-arm portion L, the opposite ends of which are each equidistantfrom the center of the pin and are adapted to support revolubly thesheaves M and M. The pin and sheaves are free to turn in the sleeve ofthe cap of the post and the sheaves support, which allows the sheaves toadjust themselves to the constantly-changing position of thehoistingropes N and N, which they support, as the sweep-beam and cageswing around its curved track. To cap and pin I pivot one end ofsweep-beam O. This sweep-beam extends to and is rigidly secured in anysuitable manner to the cage P. This-cage comprises a substantiallysquare trestle-frame of vertical timbers Q and cross-timbers R, suitablyframed together and braced by diagonal rods S. The sweep-beam alsocomprises a suitable trestleframe comprising the side pieces T andcrosspieces U, braced by diagonal rods V and a clamping-bolt W. The sidepieces of the sweep-beam, as illustrated, are bolted to crosspieces ofthe frame. Upon the top of the cage nipple 16 and a valve are connectedto the I mount in boxes X, which are secured to the cage, a shaft Y,upon which I mount two sheaves Z and Z, spacing them far enough apart toallow the top of the vacuum lift-tube 2 to pass freely between them.The-vacuum-' tube 2 is suspended from these sheaves by two wire ropes Nand N, which are attached to suitable brackets 5 and 6, riveted toopposite sides of the tube at substantially the central portion of itslength. These ropes rest on the sheaves M and M on the post 0 and extendto a hoisting-engine 7, which is set on the deck of the boat and isconnected to the boiler by the pipe 4. This hoisting-engine may be ofany suitable type. As illustrated it represents a single-cylinderfriction hoisting-engine. The vacuum lift-tube is held by the cage andropes in a substantially vertical position at all times and is loweredor raised through the cage and to and from the bed of a river by thehoisting-engine. The vacuum lift-tube comprises a straight round tubethroughout the greater portion of its length, of from one to severalfeet in diameter and with an enlarged lower terminal end of asubstantially semicircular form at and immediately adjacent to its end,which preferably blinds into a round tube before it converges into thesmaller upper portion. Across the top end of the tube I rivet a cap 8,in which I thread a valve 10, which is adapted to be opened at theproper time to admit air and destroy the vacuum. I also thread twonipples 11 and 12 to the cap, to which I secure the ends of two lines ofhose 13 and-14, bothof which extend up over and rest on the shaft Y,from which they extend over and rest on the cro ss-arm L of the pin G onthe post 0,

end of the hose and to the boiler. The hose 14 extends to and isconnected'to a waterpressure-storage tank 18, which is also set on thedeck of the boat, and is connected to a suitable nipple 19 and valve 20,which are connected to the top of the tank, At a short distance from thetop of the vacuum-tube I secure across it a diaphragm 21, which Iperforate with numerous small holes, so that when water is admitted intothe top of the tube it will be divided by this perforated diaphragm intoa shower of fine jets. Adjacent to the junction of the enlarged end withthe upperbody portion I place one or more clapper-valves 22, over holes23, formed through the shell of the tube. These valves are pivoted tosuitable cleats 24, secured to the tube, and are adapted to fit closelyover the holes. At the bottom end of the tube I hinge in any suitablemanner to its straight side a door 25, which I make in two independentparts, hinging them together soas to form a door, one

half, 26, of which is hinged to the other half, 27, to fold in bothdirections upon it.

The whole door is also hinged to swing either up .the top of the keeper.

into the tube or downward away from it, as shown by the dotted lines. inFig. 7. The door is held in position to close the end of the tube by thespring-keepers 28, which are constructed of strips of resilient steelwhich extend'a short distance along the opposite sides ofthe tube indiametrical alinement with the hinge-joint that pivots the two parts ofthe end of the door and prevents its swinging down when the door isextended straight across the entrance and its edge rests upon The boiler15 is connected to a pump 31 by a steam-pipe 32, in which is placed avalve The main discharge-pipe 34 of the pump is extended to and over theforward end of the boat and is carried up around and over and isarranged to dump into the dumping-box 35. This dumping-box is the headof a sluice-box 36. ,It is constructed of planks and is supported by asuitable trestle-Work, which, as illustrated, consists of the verticaltimbers 37 and horizontal timbers 38 and the struts 39 and the block 40,these several parts being strongly framed and secured together and tothe end of the boat. From this dump-box the sluicebox 36 continues alongthe deck of the boat to and over its opposite end. The sluice-box issupported by suitable trusses 41 and 42 and is constructed with acontinuous downward pitch that will enable the Water flowing from thepump to' properly wash all the gravel, sand, and rock that may be dumpedinto the dumping-box through the sluice-box and dis charge it overtheopposite end of the boat. At suitable intervals in the sluice-box Iplace riffles 43 to catch and hold any gold the gravel may contain. Ialso place a metal tank 18 upon the deck of the boat, which I preferablyconnect by small valved pipe 44 to the watercylinder of the pump. I pumpthis tank full of water and keep the Water under a pressure of fromfifty to two hundred" pounds per square inch in order that the pressuremay force the water through the hose 14 to the top of the vacuum-tubewhenever the valve 20 in the hose-line is opened by an operator. Asuitable valve 46 is placed in the pipe 44, and also a valve 47 isplaced in the pipe 34, to allow the operator to close either one at willand feed the full pressure of the pump through the other,as the casemight be. Thus if it was necessary or desirable'to use the full force ofthe pump to fill the tankit could be done in a very few seconds byclosing the valve 47 in the main discharge-pipe and allowing the fullpressure of the pump to pass into the tank, when the valve 4.6 could beclosed until the pres- I sure and water in the tank are exhausted;

but the pump would under proper conditions supply the tank with waterunder sufficient pressure and also the sluice-box while runnin gsteadily with both pipes being kept open to the tank and sluice-box; butif preferred and under same circumstances a separate pump could be usedto supply the tank. I also extend a valved pipe 48 from the pipe 44 tothe boiler to supply it with water. The boiler, however, if preferredmay be supplied with water by any of the commonlyknown methods.

In order to firmly anchor the. dredge-boat in a river while lifting thedeposits of gravel, sand, and gold from its bed-rock, I place at 1 eachcorner of the boat a rigid anchor which consists of a heavy verticalpost 49, slidably mounted in staples 50, secured to the sides of theboat, and in order to raise and lower these anchors I preferably providetheir inner faces with a toothed rack 51 and mount a pinion 52 and arotating operating-crank 53 in a suitable supporting-frame 54 inoperative engagement with the rack, which enables one or more operatorsto readily raise the anchors. The lower end of each anchor I preferablyprovide with a metal tip 75, which I preferably construct with aprojecting bell-shaped hood to better enable it to bed itself in thebottom of a river and hold the boat against displacing movements. To theopposite sides of the cage I secure the ends of two ropes 55 and 56,which extend to pulleys 57, that are secured to the posts 58 and 59.From these; pulleys the ropes extend to pulleys GO and 61, which arealso supported in suitable brackets 62 and 63, which are secured to thepost 58 and to the block 40, upon which the post 59 rests. From thesepulleys the opposite ends of the ropes extend to and are secured to acapstan 64, which is operatively mounted on the deck of the boat. Theropes are arranged on said capstan, so that when one rope is wound on itthe opposite rope is unwound, and the cage'is thu's drawn in either onedirection 'or the other across the bow of the boat, rolling freely uponsheaves 65, which are suitably journaled to the frame of the cage andare adapted to run on a track 66, which is preferably mounted on a chord67, placed above the heads of the operators and suitably supported byposts 58, 50, 68, 69, and 70. The capstan may also be used to draw theboat up a river by throwing oif the cage-ropes and securing a tow-lineto it.' The chord may be built up of narrowis as follows:'Aftei'anchoring the boat in a river where it is desired to dredge thedoor of the tube is first closed and'also the air-valve in its cap. Thetube is then lowered through the water until it rests on the gravel orsand lying on the bed-rock of the river. Steam is then admitted to thetop of the tube through the hose 13 from the boiler by opening the valve17 of sufficient pressure to drive out all the air and water through thevalves 22 at the lower part of the tube that thereis in the-tube aboveand adjacent to the valves. It is not necessary to drive out all the airand water down to the door, and when steam is seen to freely escape fromthe lower valve the tube is sufficiently charged with it for operation,and the steam is shut off by closing the valve 17. Water is instantlyadmitted from the water in the tank by opening the valve 20, whichallows the water to flow through the hose 14 into the top of the tubeand, being forced through the diaphragm ,fallsin a shower on the steamand instantly condenses it, creating a vacuum instantly of great power.The valves 22 are instantly closed by the suction of the vacuum, whichdraws the doorup instantly and with it enough gravel,sand, rocks, andall the gold contained therein to fill the lower end of the tube fromfour to twelve feet deep. Rock of any size that are not larger indiameter than the area of the inlet into the tube are sucked up quicklyand instantly. The forming of the vacuum and filling of the tube requirebut a second, after which the water is shut 01f from the tank. Anoperator then starts up the hoisting-engine and raises the'tube throughthe cage until its lower end is lifted above the top of the dumping-box.The cage and tube are then drawn over the dumping-box by turning thecapstan to roll the cage and tube along the curved track. The air-valve10 is then opened to admit air into the top of the tube and break thevacuum, and the door is opened by prying the keepers that support thecenter of the door at the joint simultaneously back far enough to allowthe center of the door to drop, as shown in dotted lines in Fig. 7. Thedropping of the center will pull the end 0d of the end keeper and thedoor will swing downward wide open and discharge its load of gravel 7into the dumping-box, where it is worked through the sluice-box by thewater from the pump. The door of the vacuum-tube is then again closedand the cage and tube drawn by the capstan away from it to the desiredpart of the bow of the boat and again lowered and the operationrepeated. It requires but three minutes to obtain and dump each load infrom thirty to forty feet of water, and with a tube with a mouth andlower end about four feet in diameter and a body portion about two feetin diameter from three to five tons can be raised at each lift. Iconstruct the door to structed in one piece.- In fact, a door con--structed in one piece will frequentlybe wedged in the tube by gravel.The double door being more flexible and having less continuous edgesurface is betteradapted to maintain an operative fit in the mouth ofthe tube even should it become slightly bent.

My improved vacuum lift-dredge has been constructed and used upon ascale that would rotating or sliding machine elements or parts,

and consequently it is almost impossible for it to get out of order.

I am aware that various modifications and changes in the constructionand arrangement of my vacuum-dredge can be made without departing fromthe spirit and scope of my invention. Consequently I do not wish to belimited or to be understood as limiting myself by positive expression inthe description to the exact construction shown.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is

1. The combination in a dredge of the supporting-boat, the pivotal postmounted thereon, a sweep-beam pivoted to said pivotal post, a trackcurved concentric to said pivotal post across the bow of said boat, acage comprising a trestle-framework attached to said sweepbeam andmounted to roll on said curved track, a vacuum suction lift-tubesubstantially as herein shown and described freely supported andconfined in vertical operative position by said cage and means includinga hoisting-engine for raising and lowering said vacuum-tubein said cage,substantially as described.

2. The combination in a dredge of a supporting-boat, a vacuum suctionlift-tube 0peratively supported by said boat and adapted to be raisedand lowered to and from the bottoms of rivers and comprising a long tubehaving an enlarged suction end provided with a door adapted to swingboth inward and outward and having said door divided by a hinged jointinto two parts, the outer or free part of which is adapted to fold ineither direction upon the other, means including an alternate supply ofboth steam and water for forming a vacuum in said tube; means includingone or more self closing valves for detecting the presence of anoperative volume of steam in the lower portion of said tube, and anair-inlet valve in the upper portion of said tube, substantially asdescribed.

3. The combination in a dredge of the supporting-boat having a curveddredging end, a curved track supported above the deck of said boat; apivotal post rigidly stationed on said boat concentric'to said boat, acage arranged to project over the curved end of said boat and adapted toroll on said track, a sweep-beam extending from said cage to said post,a vacuum suction lift-tube loosely inclosed and confined in an operativevertical position by said cage hoisting-ropes arranged to support saidtube in said cage; rope-sheaves mounted on said cage and supporting saidtube-supportin g ropes, a pivotal pin arranged to secure said sweep-beamto said pivotal post and provided with an upward extension containin g across-arm, a rope-sheave mounted on each end of said cross-arm andsupporting said tube-supportin g ropes and arranged and adapted toswivel and be turned by said ropes as the said cage and sweep-beam aremoved along said curved track and a hoisting apparatus on said boat towhich said ropes are 0011- nected for raising and lowering said tube,substantially as described.

4. The combination in a dredge of a supporting-boat, a curved trackthereon, a cage mounted to roll on said track and projecting beyond theboat, a pivotal support concentric to said curved track, a sweep-beamconnect in g said cage to said pivotal support,a vacuum suctionlift-tube suspended in said cage and confined thereby and controlled bya suitable hoisting apparatus and means including oppositely-disposedropes and" a power device to which said ropes are attached for movingsaid cage and vacuum tube along said curved track, substantially asdescribed.

5. The combination in a dredge of the supporting-boat,the curved trackmounted thereon; the pivotal post concentric to said track, the cageprojecting over said boat, the wheels mounted on said cage and track,the vacuum I suction lift-tube and the hoisting apparatus,

with the steam-generating boiler the waterpressure tank, the steam andwater supply pipes connecting said boiler and tank to said tube, thepump, the dumping-box and sluicebox and the capstan and ropes foroperating said vacuum-tube,substantially as described.

6. The combination in a dredge of the vacuum suction lift-tubeconsisting of a tube having a long body portion containing an enlargedsuction-or 'mouth portion, the water and steam flexible supply pipes,the steam and the compressed-water supplies, the airinlet, a door hingedto said mouth to swing both in and out and arranged to fold upon itselfin either direction at substantially the center of its width and one ormore self closing valves adjacent to the month end of said tube,spring-keepers arranged to support said door acrossthe mouth of saidtube positioned on opposite sides of said tube to engage the parts ofsaid door at their pivotal hinge, an introverted lip or'toe on saidkeepers adapted to extend under said hinge and a third springkeeperarranged to support the free end of said door across the mouth of saidtube, substantially as described.

7 A dredge for raising gold-bearing gravel from the bottoms of riverscomprising,.a vacuum suction lifting-tube having a door at itssuction-1iiouth and adapted to swing both inward and outward, means forlooking said door across said mouth, said tubehaving its upper endclosed, a supply of steam arranged to be fed at will into the topportion of said tube, a perforated diaphragm in'the top portion of saidtube, a supply of Water under pressure arranged to be delivered to thetop of said tube above said diaphragm, an air-in-

